In the next period of a continuing grant, the investigators plan: (a) A series of interrelated surveys of researchers contributing to document clusters. These surveys will examine the conceptual bases of document clusters; the degree of consensus regarding issues, persons, and documents involved in scientific changes; competition; and the evaluation of documents, researchers and laboratories. (b) A reconsideration of much of what has been written regarding the structure and operation of science. The investigators plan to determine whether their distinctive tools of analysis, which moves naturally from smaller to larger subunits of science, and their focus on biology and biomedicine has furnished new insights regarding science in general. (c) An examination of the tendency of new papers citing into a document cluster to fall into idealized Bradford distributions. This unique finding could have considerable impact on studies of scientific document collections.